Abstract

Photorefractive spatial solitons can exist in crystals like SBN, BTO and LiNbO₃ at light powers of a microwatt range. It makes such solitons a promising candidate for all-optical information technology. The photovoltaic effect in LiNbO₃ results in the self-defocusing nonlinearity and dark photovoltaic spatial solitons have already been observed in bulk LiNbO₃. Optical waveguides in LiNbO₃ with their surface doping by impurities like Fe and Cu can show much higher photorefractive nonlinearity with respect to bulk material and this nonlinearity may be strongly inhomogeneous over a waveguide depth. Besides, waveguides allow simultaneous propagation of several guided modes in the same direction. All that may result in the considerable features of spatial solitons in similar planar waveguides.

© 2000 IEEE